Treatment of hydrocarbons



2,1942. E. M. MARKS TREATMENT OF HYDROCARBONS.

Filed Juhe 11, 1940 llll-ll v Inventor Ernesi M. Mdfks By 2% Hiia rue f must a... 2, 1942 UNITED STAT 'rasa'msm or nrnao'osanons Ernest M. Marks, Lansdowne, 2a., assignor to I The Atlantic Refining Company, Philadelphia,

Pa, a corporation Pennsylvania Application June 11, 1940, Serial No. 339,846

'1 Claims. ,(01. 196-52) The present invention relates to the treatment .of hydrocarbons, and more particularly to the conversion of hydrocarbons into more valuable products by catalytic reactions involving cracking, reforming, dehydrogenation and polymerization. 1

It is a'n'object of this invention to convert high drocarbons, particularly gasoline. Hydrocarbon oils such as' gas oil, heavy distillates, petroleum residuum, tars, and the like may be advantageously converted in accordance with this invention.

It is a further object of this invention to improve the antiknock qualities. ofgasoline or naphtha distillates and to increase the lead susceptibility thereof by subjecting such distillates to reforming conditions of temperature and pressure in the presence of a catalyst. Such reforming operation involves essentially a dehydrogenation and structural rearrangement of the distillate molecules, with or without cracking and change in boiling range or volatility of the reformed distillate.

In accordance with the present invention, hy-

.drocarbons are subjected to elevatedtempera tures, under atmospheric or super-atmospheric pressure, in the presence of'a catalyst capable of promoting the conversion or reforming reaction, such catalyst comprising aluminum oxide and an alkali metal borate. In the conversion of high boiling oils, such as gas oil, into gasoline, temperatures of the order of from about 850 F. to 1050 F. and pressures up to about 3000 lbs/sq. in. may be employed, while in the reforming of gasoline or naphtha distillates for the improvee ment of the antiknock quality thereof, temperatures of the order of 975 F. to 1100 F. and pressures of the order of from atmospheric to about 1500 lbs/sq. in. may be advantageously utilized. The reaction time or space velocity may be var- I boilinghydrocarbon oils into lower boiling hyan aqueous solution or suspension of an alkali metal borate' and thereafter drying the impregnated granular material by heating. or, alternatively, finely divided aluminum oxide may beimpregnated'with an alkali metal borate solution-or suspension, and the moist material thereafter granulated or formed into suitable pellets or masses. The quantity of borate to be employed may vary from about 0.1% to 10% or more, by weight of the aluminum oxide, quantities of theorder of from about 1% to about 5% being preferred. Among the borat'es which may be .utilized are the metaborates, tetraborates, pentaborates, hexaborates, octaborates and dodecaborates of sodium, potassium and lithium. My invention may be further illustrated with reference to the accompanying drawing, which shows diagrammatically a system suitable for carrying out my process.

Hydrocarbon oil, such as gas oil, is suppliedv from a source (not shown) through valve-con trolled pipe I and is passed by means of pipe 2 I to heat exchanger 3, wherein the oil is preheated by indirect heat exchange with cracked productsfrom the catalytic chamber hereinafter described. The preheated oil is passed from heat exchanger 3 through pipe! to pump I, from which it is delivered to the tubular heating coil 0 wherein the temperature of the oilis raisedto about 950 F., under a pressure of from about 25 to about 50 lbs/sq. in. Higher pressures, oi

led, depending upon the temperature-pressure conditions and the results desired. In general the contact time or space velocity may be somewhat longer in the conversion or high boiling oils into lower boiling hydrocarbons such as gasoline, than in the reforming of gasoline or naphtha distillates for the improvement in antiknock quality thereof. Fonexample, in cracking high boiling oils, the spacevelocity may be of the order of 1 volume of charge oil per volume of catalyst per hour, whereas in the reforming of distillates, the space velocity may be of theorder of 1.5 to 4 volumes of charge oil per volume of catalyst per hour.

The catalyst to be employed in accordance with this invention comprises aluminum oxide or bauxite which hasbeen impregnated with an alkali metal borate. Such catalyst maybe precourse, may be used. In the coil I the oil is vaporized and the heated vapors are passed therefrom by means of pipe I into the upper section of catalyst chamber 8 containing a granular catalyst 0 comprising A: impregnated, for example, with 1% by weight of sodium borate (NazBiO-m- In the chamber 8 cracking of the heated oil in contact with the catalyst takes place, with the production of hydrocarbon gases, H2, cracked gasoline and gas oil, and small amounts of tar. The cracked products, at a temperature of the order of 950 F., are withdrawn from the lower section of chamber I and are passed by means of pipe iii through heat exchanger in indirect heat. exchange with relatively cool charge oil introduced through valvecontrolled pipe i and pipe 2. In the exchanger 3 the hot, cracked products are partially cooled, and thence delivered by valve-controlled pipe ll tofractionatlng column I: provided with contacting plates or trays l3. heating coil I4 and cooling or reflux coil II. The cracked products are fractionated in column ii to produce an The cracked gas oil and tar may be withdrawn from the bottom of column I! by'means oi valvecontrolled pipe It, and at least a portion thereof may be recycled, with fresh charge oil, to the tubular heating coil 6. The remainder of the cracked gas oil and tar may be withdrawn from the system through valve-controlled pipe I1 and disposed of as desired.

The gasoline vapors and gases are passed from the top of fractionating column I! and are introduced by means of pipe l8 into a second fractionating column I9 provided with contacting following examples, which, however. are not intended as limiting the scope thereof.

The results given in table were obtained by cracking, in a single pass at atmospheric pressure, various gas oils under the conditions and with the catalysts substantially as set forth. The borate-containing catalysts were prepared by impregnating granular A1203 with aqueous solutions of sodium borate and drying the impregnated trays 20, heating coil 2|, and cooling coil 22. 10 granules.

Cracking conditions Products Gas oil Catalyst Volume 'Iempera- 3223; percent Weight ture, "F. onds gasoline percent gas yiel Gravity 333 b iling range 358 F 698 F None 1, 006 v 7. l 19. 4 8. 3 D Granular Alaos 1,010 5. 8 32. l9. 0 Gransular A1z03+1% NflB4 1, 006 6. 0 36. 9 19. 3 Gransular AI2O N 82B401 1, 008 6. 1 37. 9 19. 4

1, 010 6. 2 9. 4 6. 9 1, 004 6. 9 22. 9 l4. 6 1, 006 6. 5 24. 5 15. 6 Granular A1203+5% NazBsO- 1, 006 6. 4 25. 9 15. 7

None 1, 010 6. 0 1s. 0 s. 8 Granular A1203 1, 006 6. 4 28. 2 20. 7 Granular Alz0a+1% NazB O 1,006 6. 5 31.4 21. l Granular, fused Na2B O 1,010 6.6 18.5 13. l

Herein the gases are separated from the gasoline and the latter isstabilized to obtain the desired boiling range and volatility. The stabilized gasoline may be withdrawn from the bottom of the column and passed by means of valve-controlled pipe 23 to storage (not shown). If desired, a liquid side stream comprising C; and/or C3 hydrocarbons may be removed from the column through valve-controlled pipe 24, or C4 and/or C3 hydrocarbons may be withdrawn with the uncondensed gases, 1. e., C1-C2 hydrocarbons and H2, from the top of the column by means of valvecontrolled pipe 25. If desired, at least a portion of the present invention, than are obtained under of the uncondens'ed gas and/or C3-C4 hydrocarbons may be recycled to the tubular heating coil 6 by means of valve-controlled pipe 26, compressor 21 and pipe 28.

In the operation of the catalyst chamber 8, the activity of the catalyst may be maintained or increased by the introduction of gases such as steam, oxygen, or carbon dioxide, or mixtures thereof, by means of valve-controlled pipe 29. And at such time as the granular catalyst 9 becomes fouled with carbon or tarry matter, the conversion system may be shut down and the catalyst regenerated by contacting with air or steam at elevated temperatures. Such revivifying agents may be introduced into chamber 8 through valye-controlled pipe 29 and may be withdrawn therefrom, together with the matter contaminating the catalyst, by means of valvecontrolled pipe 30.

The reforming of gasoline or naphtha distillates for the improvement of antiknock quality may be carried out in a manner similar to that similar conditions without any catalyst, or with catalysts such as A120: or fused Na2B4O'z, per se.

In order to demonstrate the advantages of employing the A12Oa-NB.2B4O7 catalysts in the reforming of gasoline for the improvement of the antiknock value and particularly the lead susceptibility thereof, the following examples are presented. A reformer stock, 1. e., naphtha distillate was vaporized and passed, at atmospheric pressure, through a chamber containing, respectively, no catalyst, A120: catalyst, and

Altos-manic catalyst, in three successive runs, the reformed gasoline being condensed and separated from the by-product gas. The operating conditions and the results obtained are shown in the following table.

Catalyst Al 0:+ 5 None None A110] N818 Temperature... 1, 050 990 1,002 Contact time ..seconds. 6. 8 7. 7 6. 5

Gas formed weight percent. 7. 4 6.4 7.3 Gasoline do. 87.9 89.7 92.7 Gasol1ne volume percent 100 88. 4 90. 9 94. 3 Gasoline, A. P. I. gravity degrees 49.3 5015 51.4 52.3 Gasoline, percent sulfur 0. 231 0.150 0. 08 0.06 Gasoline, octane number (motor method) 46 65 68 69 Gasoline, cc. Pb Eu to raise to 76 octane number 6+ 3. 5 1.35

Used catalyst-weight percent carbon deposited None 0.70 0. 27

The reformed gasoline from the AlaOa-NazBrOi treatment not only had a much higher tetraethyl lead susceptibility than that produced either by the 75 straight thermal reforming or reforming in the presence of A1203, but the yield was also substan. tially higher. Furthermore, considerably less carties, which comprises heating said hydrocarbons bon was deposited upon the AlzOs-NMBcOr catalystthan upon the A1203 used alone under substantially the same conditions, thereby permitting the former to remain catalytically active for longer periods of time than the latter.

As will be seen from the foregoing, the processes which-I have devised utilizing my aluminum oxide-alkali metal borate catalystare particularly adapted to the manufacture of gasoline, and I therefore prefer to use as a charge stock for the process, a. hydrocarbon oil boiling predominantly within orv above the gasoline boiling range, for instance, boiling predominantly within the'range of from about 100 F. to about 750 F., and preferably predominantly within the range of from about 150 F.- to about 450 F. However, processes using my catalyst can be advantageously applied to-the dehydrogenation of lighter hydrocarbons such as ethane, propane, butane, isobutane,letc., to produce oleflns for use in polymerization or other processes.

What I claim is:

1. A process for reforming naphtha to improve the antiknock quality thereof, which comprises contacting said naphtha, under reforming con- 1 ditions of temperature and pressure, with a catalyst consisting of aluminum oxide and an alkali metal borate.

2. A process for the conversion of hydrocarbons into gasoline having improved antiknock qualities, which comprises heating said hydrocarbons to a temperature within the range of from about 950 F. to about 1050 F. under superatmospheric pressure, in the presence of a catalyst consisting into gasoline having improved antiknock qualito a temperature within the range of from about 950 F. to about 1050 F. under superatmospheric pressure, in the presence of a catalyst consistin of aluminum oxide and'sodium borate, and separating from the conversion products a fraction boiling within the gasoline boiling range.

4. A processfor the conversion of a hydrocarbon stockinto other hydrocarbons, whichcomprises contacting said stock with a catalyst consisting of aluminumoxide and an alkali metal borate at a suillciently elevated temperature to eflect said conversion, said borate comprising from about 0.1% to about 10% by weight of said catalyst.

5. A process for the conversion of high boiling hydrocarbon oil into lower boiling hydrocarbons, which comprises subjecting said high boiling oil to cracking temperatures in the presence of a catalyst consisting of aluminum oxide and an alkali metal borate.

r 6. A process for the conversion of hydrocarbons into gasoline having improved antiknock qualities, which comprises heating said hydrocarbons to a temperature within the range of from about 950 F. to about 1050 F., in the presence of a catalyst consisting of aluminum oxide and sodium borate, and separating from the conversion products a fraction boiling within the gasoline boiling range.

7. A process for the conversion of a hydrocarbon stock into other hydrocarbons, which comprises contacting said stock with a catalyst consisting of aluminum oxide and an alkali metal borate at a temperature between 850 F. and 1050 F., and at a space velocity of from 1 to 4 volumes of stock per volume of catalyst per hour, said borate comprising from 0.1% to about 10% by weight of said catalyst.

ERNEST M. MARKS. 

